Grinding-fixture



J. DUPLESSIE.

GRINDING FIXTURE.

APPLICATION FILED NOV; 15, 1919.

Patented July 12, 1921.

INVENT yfiarae ATTOR NEY UNITED STATES PATENT est-ice.

-='l'OSEPI-I -DUPLESSIE, OF -PROVIDEITCE, RHODE ISLAND, ASSIG'NOR OF ONE-HALF T0 GEORGE F. ROOKIE, 0F PRQVIDENCE, RHODE ISLAND.

GRINDING-FIXTURE.

Specification Letters Patent. Patented July 12, 1921 Application filed November 15, 1919.' Serial No. 338,161.

I 0 all whom it "may concern:

and State of Rhode Island, have invented new and'useful Improvements in Grinding- I Fixtures, of which the following is a specification. 1

This invention relates to grinding fixtures used for shaping and dressing the working or cutting faces of grinding wheels.

Some of the objects of the invention are: to simplify the construction of devices of the character mentioned; to produce a device which embodies means for accurately effecting the setting of thecutting tool or diamond-tool; to produce a simple device with which grinding wheels may be operated upon to either concave or convex their workin or cutting faces or to dress the \working aces of grinding wheels parallel to their axes. With the foregoing and other objects in view the invention resides in the particular provision and arrangement of parts more fully described in the following specification and illustrated in the accompanying drawing, in which:

Figure 1 is a sectional side elevation of the device.

' Fig. 2 is a plan view thereof.

Fig. 3 is an end elevation thereof.

Fig. 4 is a diagrammatic view, illustrat- 2 ing the setting of the diamond-tool when employed for concaving the a rinding wheel.

ig. 5 is a diagrammatic view, illustrat ing the setting of the diamond-tool when employed for convexing the cutting face of a rinding wheel.

11 the use of the presentinvention, it is contemplated to move the grinding wheel toward and from the device; particularly with respect to the diamond-tool, and {it is also contemplated to move the said tool relatively to the cutting face of the grinding wheel in the shaping and dressingoperations.

Referring now to the drawing, it will be seen, that the device is to include a base 10, which is movable over a plate 11, by the use of a centering and pivot pin 12 carried by the base 10w A post 13 is provided and this post has a bore 14 which accommodates the enlarged portion of the pin 12; The

cutting face of post 1.31s also provided with a small bore 15 which receives the protruding end of a small pin 16 secured to the base 10. The post 13 has a face 17 and this face 17 is in exact alinement with the axial center of v the pin 12. j

The diamond-tool is supported and its movement is effected by parts whose construction and correlation will be presently described. A post 18 is secured to the base 10 by a screw 19. The base 10 is provided with a boss which is provided with a recess which receives the lower end of the post .18. The post 18 is provided with a small bore 20 which receives the protruding end of a; pin 21 secured to the base 10. The dia mond-tool is carried by a holder 22, which is arranged for sliding movement in a bore in the upper end of the post 18. I The holder 22 embodies a lug 23, the purpose of which will appear. The diamond-tool is designated by the numeral 24 and as stated is carried by the holder 22. In the present instance the holder is shown as being con structed of two parts; a part 25 which carries the tool 24 and a part 26 which carries the lug 23. Set screws 27 serve 'to hold the parts 25 and 26 together.

w The setting of the diamond-tool is effected by the use of an adjusting element 28 which has screw threads that coact with the screw threads of a bore 29 in the post 18. The element 28 is provided with a manipulating head 30 which has one face thereof provided with twenty-five graduations 31. The threads embodled by the element 28 are forty to the inch. The head 30 is so constructed as to provide an annular portion 32 which is received by a groove 33 in the end of the part 26 of the holder 22, and it therefore follows, that movement may be imparted to the holder 22 by the manipulation of the head 30. Inasmuch as one complete turn of the element 28 is the equivalent of the twenty-five degrees into which-the transverse face of the head 30 is divided, and inasmuch as the threads of element 28 are forty to the inch; one complete turn of the head 30 in either direction will move the tool 24 one-fortieth of an inch. The movement of the head 30 one degree in either direction in effect indicates, 7

. point of the tool 24 touches the face-170i the post 13 as arranged on the pivot pin 12, is a certain or known dimension. As

hereinbefore stated, when the post 13 is arranged-on the pin 12, the face 17 will aline with the axial center of the said pm 12. Inasmuch as there is a known dimension when the point of the cutting tool 24 is in a plane coincident with the axial center of the pin 12, further movement of the tool 24 to either side 'of the axial center of'the pin 12: may be ascertained by noting the change whlch will be shown. by a re-measuremen't of the distance over all ,of the lugs 23 and 35. A set screw 34 serves to hold the tool holder adjusted in different positions.

As shown in Fig. 4 of the drawing, the

" tool 21 is moved to the left of the axial center of the pin 12, and in 'such position of the tool, when the device in its entirety is moved about the pivot pin 12,- the working face of a grindln wheel may bev concaved. The position o the .tool 24 as shown in Fig. 5 is such that when the device in its entirety is moved about the pivot pin 12, the working face of a grinding wheel I may be convexed. It will be manifest that the working face of agrinding wheel may be concaved or convexed accurately in accordance with specified dimensions; that the device embodies means with which such results may be readily accomplished.

What is claimed as new is I 1. A grinding fixture embodying a diamond-tool, a pivot having one facethereof in alinement with the axial center of said pivot, means for effecting movement of said tool with relation to said face, andmeans permitting the accurate determination of the distance of movement of said tool for the accurate setting of said tool, the last mentioned means including relatively separable measuring lugs. v i

2. A grinding fixture embodying a diamond-tool, a pivot on Which the fixture as a whole moves, a base, a post havmgameasurin lu the said st bein ositioned on sii id vise, a slidable holder fo the diamond-tool, said holder having a measuring lug movable with relationto said first mentioned lug, as and for the purpose specified.

'3. A grinding fixture embodying a dim mond-tool, a pivot, a slidable holder for said tool, a post having one face thereof in alinement' with the axial center of said pivot,

means including a micrometer for effecting the movement of said holder to different positions and means for securing the holder in. different positions. 1

4. A grinding fixture which has pivotal movement comprising, a base, a pivot pin carried by said base, a post adapted to be located on said pin, said post having a face thereof in alinement with the axial center signature.

' JOSEPH DUPLESSIE, 

